How To Send a Confirmation Email In Php?

To Send a Confirmation Email In Php script, follow the guided instructions given below.

html body  php  //create a variable we can use to determine if the user input is good or not  $formOk=true;  //Check that a first name has been entered  if (empty($_POST['First_name'])) {      echo 'First name is required';      $formOK = false;  }  //Check that a last name has been entered  if (empty($_POST['Last_name'])) {      echo 'Last name is required';      $formOK = false;  }  //Check that an email was entered  if (empty($_POST['Email'])) {      echo 'Email is required';      $formOK = false;  }  //Check that a password value has been entered   if (empty($_POST['Password'])) {      echo 'Password is required';      $formOK = false;  }  //Check for password value and if it matches the retyped password  if ($_POST['Password'] != $_POST['confirm_password']) {      echo 'Passwords do not match';      $formOK = false;  }  //Check that a city has been entered  if (empty($_POST['City'])) {      echo 'City is required';      $formOK = false;  }  //If all the information entered is valid if ($formOK == true) {      $conn = mysqli_connect('localhost', 'dbxxxxx', 'XXXXXX', 'dbxxxxx') or die('Could not connect: ' . mysql_error());                $passwordHash = sha1($_POST['Password']);      $sql = "INSERT INTO users (First_name,Last_name,Email, Password,City,Province) VALUES ('$_POST[First_name]','$_POST[Last_name]','$_POST[Email]','$passwordHash','$_POST[City]','$_POST[Province]')";      $to=$_POST['Email'];      $subject="Email Confirmation";      $message="This is a confirmation email";  //Use the mail function to send the confirmation email      mail($to,$subject,$message);  //Show the user that they have been added. //Close the connection to the database.      mysqli_query($conn, $sql);      echo "User has been added";      mysqli_close($conn);  }  else {      echo 'Click a href="javascript:history.go(-1)">HERE/a to go back and adjust your entry.';  }  ?>  /body  /html